Children as young as three are being treated for obesity, an expert warns.
Lack of exercise is blamed on the rise in obesity
In a normal child 20-25% of their body weight will be fat but specialists report that they are seeing toddlers with up to 50% body fat.
Professor Tim Barrett of Birmingham University says that if these children are not treated they risk developing heart disease and diabetes.
His concerns follow the case of eight-year-old Connor McCreaddie who weighs more than 14 stone (89kg).
Professor Barrett, a paediatrician, says that the problem only began five years ago.
He is currently dealing with four or five cases of clinically obese children under the age of four, who have been referred to him by GPs.
He says his colleagues across Birmingham are dealing with similar numbers of young obese patients.
"They are always absolutely delightful. They sit there smiling at me, usually with a bag of crisps and can of pop, because that's their basic diet," said Professor Barrett.
He blamed a poor diet and lack of exercise for the problem.